1. Field of the Invention
The present invention relates to an apparatus for depositing folded signatures on a transport device, with a rotating extracting cylinder which grips signatures individually from a stack and transfer the signatures to a first rotating opening cylinder and a second rotating opening cylinder which open the gripped signatures at the edges opposite from the fold and drop the signatures on the transport device, with a clamping device disposed on the first opening cylinder which grips the signatures at a respective projecting edge to open and transport the signatures, and with means which grip the above-referenced edges in the extracting cylinder from behind and transfer the edges to the clamping device.
2. Description of the Related Art
An apparatus of this type is disclosed in CH-A-408 065 by the applicant. The first opening cylinder includes a cylinder sector which has a greater radius than the remaining cylinder sector of the opening cylinder and which engages in the rotation range of the extracting cylinder. The cylinder sector also grips the rear end of a signature from behind and grips a protruding edge with a clamping device. The signature is subsequently opened in cooperation with the second opening cylinder and drop to on a transport device which may be implemented as a collecting chain. Such devices have operated satisfactorily in practice. The cylinder sector with the greater radius, however, occupies a comparatively greater portion of the circumference of the extracting cylinder which makes this device less efficient.
A similar device is disclosed in JP-A-0 42 69 594. The extracting cylinders and the two opening cylinders or hear driven by dedicated synchronous motors. The rotation speed of the towns can be adjusted with a controller. The signature is gripped by a cylinder sector of the first opening cylinder. This design decreases the problems associated with the intermeshing cylinders.
U.S. Pat. No. 4,875,669 describes a device which includes three rotatable arms arranged on the extracting cylinder up which push the rear edges the signature radially outwardly for transfer to the opening cylinders. With this device, several signatures can be transported simultaneously on the extracting cylinder. The extracting cylinder, however, also includes control arms and is therefore expensive to fabricate and subject to malfunction. In addition, the clamping device on the first opening cylinder makes the arms more difficult to synchronize.